1. Field of the Invention
The present invention relates in general to the field of information display, and more particularly to a system and method for information handling system native and docking support of Digital Video Interface display signals.
2. Description of the Related Art
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
As the technology available for information handling system hardware and software components advances, the amount and types of information presented to users have increased in number and complexity, resulting in increased demand for high resolution displays. One difficulty with the presentation of information from an information handling system to a high resolution display is that higher resolutions tend to transfer larger quantities of display information at more rapid rates that have outgrown the capacity of the analog VGA standard. In order to meet consumer display quality demands, information handling system manufacturers have begun to implement the Digital Video Interface (DVI) standard. Typically, DVI is generated on a graphics memory controller hub (GMCH) or graphics processor unit (GPU) as a Digital Video Output (DVO) to a Transition Minimized Differential Signaling (TMDS) transmitter that outputs a serial signal for transmission to a display. TMDS signals are communicated at a relatively high speed of 1.65 GB/s, making signal integrity an important consideration in the communication of a TMDS signal from an information handling system to a display.
One difficulty that arises with implementation of DVI in portable or notebook information handling systems is whether to provide a DVI connector on the system itself or on a docking station. Typically, users of portable information handling systems interface external displays through a docking station that connects to the information handling system through a single connector. However, in some circumstances users of portable information handling systems desire a DVI connector on the information handling system itself, such as to connect with a projector during a presentation. Generally, daisy chain routing of a TMDS signal from a transmitter to a DVI connector on an information handling system and then to a docking station DVI connector results in excessive signal integrity degradation so that supporting separate DVI connectors on an information handling system and docking station tends to require separate TMDS transmitters for each DVI connector and a more complex software solution to provide the same display surface data to be displayed from a TMDS port for docked and undocked configurations. However, the use of separate transmitters is costly in the space consumed on a portable information handling system, in the expense of an additional TMDS transmitter and in the power consumed.